In manufacturing of a semiconductor device, various treatment apparatuses (semiconductor fabricating apparatuses) are employed to perform treatments, such as oxidation, diffusion, CVD (chemical vapor deposition) and annealing, to process objects such as semiconductor wafers. As one of such apparatuses, a batch-type vertical heat treatment apparatus capable of heat-treating plural wafers at one time is known.
The vertical heat treatment apparatus includes: a load port (i.e., loading and unloading part) provided at the front portion of the vertical heat treatment apparatus for loading and unloading a carrier (also called “carrying container” or “FOUP”) containing plural wafers into and from the vertical heat treatment apparatus; a storage shelf that stores plural carriers loaded into the vertical heat treatment apparatus via the load port; a heat treatment furnace that accommodates a boat (i.e., holder) holding plural wafers at multiple levels to perform a predetermined heat treatment to the wafers; and a FIMS port (i.e., transfer part) that supports thereon a carrier for transferring wafers between the boat and the carrier.
A vertical heat treatment apparatus: in one example, has a load port only at the lower portion thereof; in another example, has a load port only at the upper portion thereof; in another example, has load ports at both upper and lower portions thereof (See JP2004-119614A, for example).
In a vertical heat treatment apparatus, it is desirable that the apparatus can store therein carriers as many as possible, and that the apparatus is adapted for various carrier-storing patterns, in view of shortening of treatment time and improvement of throughput. However, in conventional vertical heat treatment apparatuses, only a shelf is prepared as a space for storing carriers, and thus a limited number of carriers may be stored in the apparatus. Moreover, the load port plays only a role of loading and unloading carriers into and from the vertical heat treatment apparatus. It should be noted that it is not preferable to increase the size (or footprint) of the vertical heat treatment apparatus for the purpose of increasing the space for storing carriers.